Pediatrician Dr. Benjamin Spock interacting with children in 1979. His bestselling book, "The Common Sense Book of Baby and Child Care," was published in 1946 and helped alter ideas about child rearing.

In the pantheon of parenting gurus, Dr. Spock appears to have legendary staying power. Nowadays, there are shelves full of niche parenting books, offering advice on raising twins or singletons, high-spirited toddlers and attention-starved middle children. But this week, the good doctor weighed in yet again with his generalist and commonsensical pronouncements. More than 60 years after the inaugural edition of Dr. Spock’s Baby and Child Care was published, the ninth edition hit the shelves.

Benjamin Spock died in 1998, so this most recent tome is the sum of Spock’s original content and that of similarly minded authors. At least half the book is still in Spock’s own words, but there’s new information on the importance of outdoor play and nature, on autism, ADHD, immunizations and raising children who aren’t so darn materialistic. The previous eight editions have sold more than 50 million copies.

It’s been seven years since the previous revision, and much has changed since then, particularly in terms of psychosocial factors that may affect development. “We didn’t have the same kind of economic crisis we are in the middle of going through,” says co-author Robert Needlman, an associate professor of pediatrics at Case Western Reserve University and a pediatrician at MetroHealth Medical Center in Cleveland. “These things have profound effects on families and children.”

As a result, there is updated information on how to raise children by taking a less materialistic approach. “The book is trying really hard to make people understand you can be a really good parent without buying a lot of stuff and spending huge amounts of money on things,” says Needlman.

The field of brain development has also progressed considerably. When Spock first wrote his parenting guide, he didn’t mention autism and ADHD; the latest version discusses both subjects in detail. Considering the amount of electronic media today’s kids consume, it’s not surprising that the book also devotes a chunk of text to persuading parents to limit screen time. “For young kids especially, the most important and effective stimuli are human as opposed to electronic,” says Needlman. “I think that will be true for a very long time.”

Along those lines, there’s a new section on the role of nature in childhood. “It’s about helping parents realize kids need time to dig in the dirt and see things grow,” says Needlman. “Computers aren’t really a substitute for that.”

Nutrition also gets an overhaul, with the authors placing more of an emphasis on vegetarianism. But cutting back on meat alone isn’t the solution; kids rate pizza as their favorite food, and even plain cheese pies are loaded with saturated fats. Pizza has its place, but parents are advised to rely less on meat and cheese, both of which are high in saturated fat, and dish up more beans and veggies.

“The Spock philosophy is, Don’t tell parents what to do and don’t guilt them.’ You lay out the information and let parents make the decisions, so there’s a lot of gently prodding people to consider other foods.”

With all the specialized parenting guides out there, why turn to a pediatrician who’s been dead for over a decade? Needlman, who was tapped by Spock’s widow to work on this latest edition, says it’s simple: “Spock’s take was parents are different and kids are different, and parents need insight, not instructions, into how kids work,” says Needlman.

That was a very radical departure from conventional wisdom in the first half of the 20th century, which advised parents to feed their babies on a strict schedule and never to pick up a crying infant for fear of spoiling him.

Spock pooh-poohed that approach. Instead of fretting about indulging babies, Spock encouraged parents to heed their instincts and be more affectionate with their kids. “What makes Spock’s book worth fussing about is it is still the best source for the kind of parenting advice that respects parents’ intelligence,” says Needlman. “It’s trust yourself as opposed to listen to the expert.”

Bonnie Rochman is a reporter at TIME. Find her on Twitter at @brochman. You can also continue the discussion on TIME‘s Facebook page and on Twitter at @TIME.